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Cosmic Jets. Neutrinos. as sources for high-energetic. Andreas Müller http://www.lsw.uni-heidelberg.de/~amueller/. Theoriegruppe Prof. Camenzind Landessternwarte Königstuhl, Heidelberg. 12. 12. 2002. Overview. Motivation The AGN paradigm Jet physics:
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Cosmic Jets Neutrinos as sources for high-energetic Andreas Müller http://www.lsw.uni-heidelberg.de/~amueller/ Theoriegruppe Prof. Camenzind Landessternwarte Königstuhl, Heidelberg 12. 12. 2002
Overview • Motivation • The AGN paradigm • Jet physics: Formation, collimation, morphology • Particle acceleration • Jet simulations and sources • Relativistic leptonic and hadronic Jets • Ultra-relativistic GRB Jets • Cosmic Rays • Proton Blazars • AGN neutrino flux • Microquasars • Microquasar neutrino fluxes • Implications of UHE neutrino astronomy • Surprise!
p + p _ p+ + X CC _ p- + X CC EN > 300 MeV _ p0 + X NC p + g_ p0 + p photopion production (inelastic scattering) p + g_ p+ + n escape via isospin flip p-_ m- + nm p+ _ m+ + nm p0 _ g + g m-_ e- + ne + nm m+ _ e+ + ne + nm Motivation hadrons neutrinos
Cosmic neutrino sources • Galactic sources: Sgr A* SN SNRs Microquasars • Extragalactic sources: GRBs GRBRs AGN Jets constraint: AMANDA threshold 50 GeV
IR UV Xg opt AGN type 1 multi-wavelength spectrum 3 bumps
Jet formation - theory • Kerr black hole vital: frame dragging in ergosphere • ergospheric dynamo: creates and sustains toroidal magnetic flux and currents • extraction of rotational energy of Kerr hole • outgoing wind driven by MHD Alfvén waves • reconnection: plasma decouples from magnetic field as approaching to horizon (restatement of No-Hair theorem) • magnetized accretion disk: energy of accreting plasma powers the wind (B. Punsly, BH GHM, Springer 2001)
Jet formation - simulation log(r) from 0.1 to 100 color-coded, arrows: velocity, solid line: magnetic field parameters: a = 0.95, t = 65 rS, vJet = 0.93c, g = 2.7 (Koide et al., 2001)
Lorentz force: electric current in jet plasma • toroidal mag. field BF • FII: acceleration • total magnetic field B • FI: collimation additional dependencies: • gas pressure • centrifugal forces • ambient pressure MHD-Jet collimation and acceleration
Particle acceleration • Lorentz forces and gas pressure in Jets • Fermi acceleration • 1st order: relativistic shock waves propagate through turbulent plasma accelerating charged particles • 2nd order: stochastical acceleration of particles when diffusing through turbulent plasma • macroscopic kinetic energy of plasma transfered to few charged particles! • shock fronts Jets: internal shocks, bow shock GRBs: fireball shock SNs/SNRs: blast wave shock (ApJS 141, 195-209, 2002, Albuquerque et al.)
Jet simulation cocoon shocked ext. medium bow shock r t = 1.64 Myr M. Krause, LSW HD
Jet – emission knots periodic bright knots associated with inner shocks (rarefaction & compression) complete linear size: 159 kpc z = 1.112
Radio Jet – Cyg A VLA jet and counter-jet, core, hot spots, lobes Synchrotron emission in radio from relativistic e- false color image: red is brightest radio, blue fainter. D ~ 200 Mpc
X-ray Jet – Cyg A Chandra X-ray cavity formed by powerful jets hot spots clearly visible in 100 kpc distance away from core surrounding is hot cluster gas T ~ 107 to 108 K resulting topology: prolate/cigar-shaped cavity
Relativistic hadronic and leptonic Jets • 3 models: BC – baryonic cold LC – leptonic cold LH – leptonic hot • leptonic species: e-e+ (rel.) • hadronic species: p, He (th.) • Relativistic Hydrodynamics (RHD) in 2D • NEC SX-5 Supercomputer • jet kinetic power: 1044 to 1047 erg/s • typical lifetime: 10 Myr • surprisingly similar dynamic and morphology! log(r) (Scheck et al., 2002)
Relativistic hadronic and leptonic Jets lowest G highest G Lorentz factor G after 6.3 Myr (Scheck et al., 2002)
1.8 s after explosion • = 10 a v = 0.995c • axis unit: 100 000 km • contour: • vr > 0.3c • eint > 0.05 e0 • Jet: • 8° opening angle • Jet core: • 99.97% c Relativistic GRB-Jet G outer stellar atmosphere stellar surface M.A. Aloy, E. Müller; MPA Garching
Cosmic Rays • ultra high-energy CR: 1019 eV < E < 1020 eV • 1st reported by Fly‘s Eye, AGASA air shower detectors • CR sources: homogeneous distributed and cosmological • candidates: GRBs (cp. BATSE @ CGRO) AGN Jets: photo-produced p0 decay to gg • CR sources generate UHE protons • each has power-law differential proton spectrum: dN/dE ~ E-a • spectrum insensitive to source evolution with z and cosmological parameters (H0) • observable constraint: 1.8 < a < 2.8 • often assumed: a = 2.0 • neutrinos overtake a-value if secondary from p-p reaction! • in p-g reactions weighting with photon power law • WB limit: neutrino flux limited by parental proton energy! (ApJ 425, L1-L4, 1995, Waxman; Waxman & Bahcall, 1999, 2001)
CR spectrum ECR > 1017 eV (astro-ph/0011524, Gaisser)
non-conservative approach! (alternative to IC of accretion disk thermal UV emission on accelerated electrons) • proton acceleration in most powerful AGN Jets • power law distribution: np(Ep)~Ep-s • protons hit • p-target yields n: Qppn(En)~ En-s neutrino production rate • g-target yields: • CMB: Greisen-Zatsepin-Kuz‘min cut-off (1966): • Ep < 1019 eV „intergalactic proton“ • Synchrotron spectrum with ng(Eg)~ Eg-a: Qpgn(En)~ En-(s-a) • protons undergo unsaturated synchrotron cascades and emit Xg, electrons: synchrotron contributions • drastic steepening of cascade spectrum above Eg ~ 100 GeV: absorption of Xg by host galaxy IR-photons from dust • BUT: neutrinos not dampend! Proton blazar model (astro-ph/9306005, 9502085, 0202074, Mannheim)
Proton blazar 1218+258 Data: NED Montigny et al. 1994 Fink et al. Whipple group • fit parameters: q = 7° gjet = 5 gp = 2 x 109 d = 7 B = 4 G (astro-ph/9502085, Mannheim)
Quasar 3C273 –predicted neutrino flux • nmfluxes • compared with SNRs and Coma galaxy cluster • n oscillations neglected! (astro-ph/0202074, Hettlage & Mannheim)
Microquasars Chandra homepage
MicroquasarCyg X-3 • discovery in 1967 (Giacconi et al.) • companion: massive Wolf-Rayet as can be observed from wind in I- and K-band (van Kerkwijk et al., 1992) • orbital period: 4.8 h derived from IR and X-ray flux modulation via eclipses (Parsignault et al, 1972; Mason et al., 1986) • TeV source! • optical observation possible (extinction in Galactic plane) • CO nature: NS of ~ 1 M8 with 10-7 M8/yr and WR with 15 M8 (Heuvel & de Loore, 1973) vs. stellar BH with WR of 2.5 M8 (Vanbeveren et al., 1998; McCollough, 1999) • 1st only one-sided jet (Mioduszewski et al., 1998)
MicroquasarCyg X-3 • evolution sequence of bipolar radio jet • binary system: Wolf-Rayet and NS/BH • D = 10 kpc • q = 14° • b = 0.81 (Mioduszewski et al., 2001) VLBA
MicroquasarGRS1915+105 • evolution sequence of one-sided radio blob • binary system: normal star and BH • GBHC: MBH ~ 14 M8 • D = 12.5 kpc • q = 70° • b = 0.92! (Mirabel & Rodriguez, 1994) VLA
most enigmatic and still unique object in the sky! • CO: neutron star or black hole? • companion: OB star with 20 M8 • mass loss rate: 10-4 M8/yr (wind) • orbital period: 13.1 d • persistent source • 1977 discovered, constellation Eagle • d = 3 kpc • i = 79° • b = 0.26 (nearly const!) • no continuous jet: bullets • slow wobbling period: 164 d • surrounded by diffuse nebular W50 (possible SNR) • jet: strong, variable Ha line emission • emission lines doubled • estimated: Ljet ~ 1039 erg/s SS 433 - data (ApJ 575, 378-383, 2002, Distefano, Guetta, Waxman & Levinson)
~ 20 cm SNR W50A SS 433
SS 433 in X-rays T ~ 5 x 107 K d ~ 5 x 1018 km Chandra homepage 11.12. 2002
SS 433 - theory • bullet ejection model • timescale: non-steady shocks in sub-Keplerian accretion flow • bullet shooting interval: 50-1000 s • donor matter rejection by centrifugal force • radiation pressure supported Keplerian disk • 15 to 20% of accreted matter is outflow: mean outflow rate: 1018 g/s • mean accumulated bullet mass 1019 - 1021 g (moon 1021 g) • bullet formation by shock oscillations due to inherent unsteady accretion solutions (astro-ph/0208148, Chakrabarti et al.)
Microquasars - parameters Sn Ljet i G • all jets resolved in radio (~280 known XRBs, ~50 radio-loud) • SS 433 not present: more complicated model (ApJ 575, 378-383, 2002, Distefano, Guetta, Waxman & Levinson)
Microquasars – m event predictions pulse periodic strong persistent: 1 yr integration time Dt (ApJ 575, 378-383, 2002, Distefano, Guetta, Waxman & Levinson)
Implications of UHE neutrino astronomy • determination of two-component jet plasma: fixing the ratio of leptonic to hadronic species „Detection of n emitted by AGN would be a smoking gun for hadron acceleration.“ (Hettlage & Mannheim) • deeper insight in Jet physics generally • better understanding of microquasar physics • detection of low-inclined radio-hidden microquasars • verification of neutrino oscillations on cosmological scales • clarification of neutrinos as Majorana particles • CR mapping • new issues for the origin of UHE cosmic rays
Most distant AGN Chandra SDSS quasars in 13 billion lightyears distance emission starts as Universe was 1 billion years old! MBH ~ 1010 M8 (Brandt et al., 2002)